Elevator-door-locking gear



Nov. 26, 1929. T. H. J. SIMMONS ET AL 1,736,805

ELEVATOR DOOR LOCKING GEAR Filed May 27. 1926 8 Sheets-Sheet l i I }lNVENTOR5 I ATTORNEY Nov. 26, 1929. T. H. J. SIMMONS ET AL ELEVATOR DOOR LOCKING GEAR Filed May 27. 1926 8 Sheets-$heet 2 x g M W 4P m U Hu l l l l l lH Hl l l l Hl lH l l lHI l l lHHl l l l HH II I I I I I HI H HM H H H HV IHU I HHHI I H HHHH\ I q a z #4 w L m mm #2 1M. 0 0 Ci v M WW J 7/ w a F F ATTORNEY Nov. 26, 1929. T. H. J. SIMMONS E L ELEVATOR DOOR LOCKING GEAR 8 Sheets-Sheet 3 Filed May 27. 1926 IIIIIIIIIIIIIIIIIIIIIIIIIII ]INVENTOR5 4MMM11- ATTORNEY Nov. 26, 1929.

T. H. J. SIMMONS E L ELEVATOR noon LOCKING GEAR Filed May 27. 1926 8 Sheets-Sheet INVENTORS ATTORNEY 8 Sheets-Sheet 5 Y E N m m \INVENTORS v E III! I. E

T. H. J. SIMMONS ET AL ELEVATOR DOOR LOCKING GEAR Filed May 27, 1926 Nov. 26, 1929.

Nov. 26, 1929.

T. H. J. SIMMONS ET AL ELEVATOR DOOR LOCKING GEAR Filed May 27. 1926 8 Sheets-Sheet 6 ,9 454 m o o o ATTORNEY Nov. 26, 1929. T. H. J. SIMMONS E AL 1,

4 ELEVATOR DOOR LOCKING GEAR Filed May 27. 1926 8 Sheets-Sheet 8 llliillllll 'IIIIIITIIIII will 111111111 INVENTORS BY ATTORNEY Patented Nov. 26, 1929 UNEE THOMAS HUBERT JOHN SIMIMONS AND EDXVARD CLEMENCE, OF LONDON, ENGLAND, ASSIGNORS TO OTIS ELEVATOR COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY ELEVATOR-DOOB-LOCKING GEAR Application-filed. May 27, 1926, Serial No. 112,021, and in Great Britain September 9, 1925.

This invention relates to locking gear for the landing doors of elevators and more par ticularly of electric elevators controlled by the automatic push-button system; such locking gear is intended to ensure that the car cannot be moved away from a landing until the door has been properly closed and also to prevent any landing door being opened unless the car is present at the landing in question. Known forms of locking gear usually include electrical contacts forming part of the operating circuit, the movements of the door or of its latch actuating a switch member to open and close the circuit as required, togethor with means for closing or securing the door latch by the movement of the car away from the landing. lVith such devices occasional failures may occur, due principally to me chanical faults, such as the breakage of a spring, especially when the locking movement is of a permissive, i. e. non-positive, nature.

The present invention has for its object to provide an improved door locking gear for elevators, in which all the movements necessary for openin-.the doo-r are interconnected'in a positive manner, andin which the opening of the door at any landing is made conditional not only upon the presence of the car at the particular landing but also upon the car being intended tostop at that landing.

Another object of the invention is to combine the door latch with an electrical car-locking device, the latch-actuating member having an initial opening movement possible at all times, and asecondary consequential movement which prevents the restarting of the car and unlocks the door, allowing the final movement which completes the unlatching oi the door; this'final position is maintained by a positive mechanical interlocking device which remains in engagement so long as the door remains open. A further object is to determine by electromagnetic controlling means the conditional unlocking of the landing door and interruption of the operating circuit by the secondary consequential movement of the latch-actuating member, such electromagnetic controlling means depending for its operativeness upon the stopping of the elevator" car at the landing inquest-ion.

The invention'is hereafter more fully described with reference to the accompanying drawings, which illustrate applications of the door locking gear to an electric elevator controlled by the well known push button system; in these drawings, I

Figure l is a schematic representation of a push-button elevator system embodying elec tromagnetic floor switches and a floor controller of well known type; the door locking gear is shown diagrammatically to. illustrate the electrical connections of the electromagnetic controlling means. U

Figure 2- is an elevation ofone of the land ing doors, as seen from the. elevator car in the hatcliway, according to the preferred construction of door locking gear.

Figure 3 is a plan view of Figure 2.

Figure 4 is an edge yiew of the door, seen from the left of F igure2.

Figures 5 to 7 represent on a larger scale the details-of the construction illustrated in Figures 2 to 4. I: v

Figure 5 being a part elevation corresponding to Figure 2, 'andshowing the vertically slidable bolt for retaining the door in closed position, one of the handles .for releasing the retaining bolt, the lockbox vcontaining the armature of the electromagnetic controlling means, and the mechanical interlocking (device.

Figure 6 is a view. in section on the line 6-6 of Figure 5; and 1 Figure 7 is a similar view in section on the broken line 77 of Figure 5.

. Figure 8 is a view corresponding to Figure 7, showing the parts in the position occupied after the initial movement of the door-- handle.

Figure 9 is a similar view, showing the parts in the position occupied after the attraction of the armature.

Figure 10 is a similar view, showing the parts in the position occupied after the further movement of the handle.

Figures 11 and 12 represent the two sets of electrical contacts in the lock-box, in the position corresponding with Figure 8.

Figure 13 represents one set of contacts in the position corresponding with Figure 9.

Figure 14 represents the other set of contacts in the position corresponding with Figure 10.

Figure 15 is a plan of Figure 6, showing the armature in normal unattracted position.

Figure 16 is a detail in elevation of a corner of the elevator car roof, showing one arrangement of the door-controlling electromagnet thereon.

Figure 17 is a plan of Figure 16, as seen from below.

Figures 18- to 20 represent details of an alternative construction of door-locking gear,

Figure 18 being a part elevation corresponding to Figure 5;

Figure 19 is an elevation of the same, seen at right angles to Figure 18; and

Figure 20 is a plan view of Figure 18, showing the armature in the attracted position.

Fi re 21 is a detail similar to Figure 16, showing an alternative arrangement of doorcontrolling electromagnet.

Figure 22 is a plan view ofv Figure 21, as seen from below.

Figure 23' is a sectional elevation, showing the application to the locking gear illustrated in Figures 5 to 7, of an emergency device for releasing the landing doors in case of failure of the electromagnetic controlling means.

Figure 24 is a front elevation of the means for operating this emergency device.

Referring to Figure l, the elevator car C is suspended by hoisting cables 1, which run over a driving sheave 2 secured to the shaft 3 driven by a motor M. The usual counterweight CWT' is secured to the ends of the cables opposite to the car, and the customary electro-mechani'cal brake (not shown) is pro vided for stopping the motor.

The electromagnetic reversing switches are designated R and R";- the switch R controls the motor for descending direction of car travel, and the switch R for ascending direction of travel.

The automatic push button ap aratus comprises car push-buttons 4, 4, 4; hall pushbuttons 5, 5, 5", floor switches 6, 6, 6", a non-interference and car-holding switch 7, car-gate contacts 8, door-contacts 9, 9, 9", and a floor controller F, which may be of any well-known construction. In the diagram only three landings L, L, L, are represented, but it will be obvious that the elevator car maybe arranged to serve any desired number of landings.

At each of these landings, there is provided a door I), D, D, for guarding the doorway opening when the elevator car is absent from the landing. As illustrated the door D (see Figures 2 to 4) is hung upon brackets 10, 10 fitted with rollers 11, 11' travelling upon a horizontal guide ra l 12,

whereby the door may be opened by lateral sliding movement to clear the doorway W and give access from the landing to the elevator car or vice versa; in Figure 2, one end of the guide rail 12 is shown reduced in height to provide a shoulder 13. The lower edge of the door is fitted with guide-pieces 14, 14', 1 1, adapted to slide in a slot 15 formed in a sill-plate 16 extending across the width of the doorway. Normally, the door is retained in closed position by a vertisally slidable enclosed bolt 17, of which the lower extremity 18 is adapted to enter a socket 19 at one end of the sill-plate 16 of the doorway; the upper end of the bolt also engages with the shoulder 13 upon the guide rail 12, as hereafter explained. In order to release the door-retaining bolt 17, there are provided suitable handles 20, 20 on opposite sides of the door, these handles being rotatable upon studs 21, 21 and fitted with lingers or crank pins 22, which engage with the bolt 17. As shown in Figure 5, the bolt 17 is divided at the level of the handles 20, 20, the two parts being connected together by a block 23 having an aperture 24 in which the fingers 22 are engaged.

At the top of the door D and immediately above the bolt 17 there is provided a housing 25 rigidly secured to the door and fitted with a detachable cover plate 26. The upper end of the bolt 17 passes vertically into this housing, inside Which it is secured to a slotted block 27 having an upwardly extending offset arm 28, the extremity of which is pivotally connected by a pin 29 to the slotted ends of a forked crank arm 30. This crank arm 30 is slidably mounted upon a shaft 31 extending across the doorway, preferably above the guide rail 12, the further end of the shaft being supported by a hanger 32 attached to the side of the doorway; the remainder of the shaft 31 is shown as of square cross-section, the crank arm 30 having its boss 33 apertured to a corresponding form so as to slide freely along the shaft while remaining fixed in angular relation thereto. The slotted block 27 embraces the guide rail 12, the shoulder 13 normally engaging one side of the block; consequently until the bolt 17 is raised to lift the block over this shoulder, its engagement with the guide rail prevents the opening of the door.

At the side of the doorway W towards which the door moves in closing, and at about the same level as the housing 25 fixed upon the door, there is mounted a lock-box 31 made of non-magnetic metal and fitted with a detachable cover 35. The shaft 31 passes through the housing 25 into the lockbox 3 1, inside which it is provided with a cam 36 and with a cylindrical barrel 37 of insulating material, both fixed rigidly upon the shaft as by set screws; the extremity 38 viii of the shaft 31 is supported by a rotatable bush 39 in the wall of the lock-box.

The cam 36 (see Figure 7) is of part-circular contour, the remainder of its periphery comprising two flat faces 40, 41 at right angles to one another, and an oblique face 42 connecting with the circular contour. Upon the face there is secured, as by screws, a plate 43 having an overhanging edge turned up towards the oblique face 42 to form a nose 44. The wall of the lock-box adjacent to the cam 36 has secured therein, as by screwing, a pin 45 which supports a bell crank lever 46, 47, the latter being retained by a washer 48 and split pin or other suitable means, so that the lever 46, 47 can rock upon the pin 45, the arm 46 of the lever extending across the bottom of the lock-box for a purpose hereafter explained, and the arm 47 being in alinement with the cam 36. Upon the side of the lever arm 47 facing the cam there is formed a projecting lug 49, adapted to co-operate with the cam faces as hereafter described. The free end of the lever arm 47 is enlarged to form an armature 50, extending across almost the entire width of the interior of the lock-box, the lever and armature being made of mild steel or other suitable magnetic material. As shown most clearly in Figure 15, the sides of the armature 50 are provided with horn-pieces 51, 51 having bevelled faces 52, 52" on their outer edges.

Upon the front of the lockbox, that is the side directed towards the hatchway, there are secured, as by screws, two parallel bars 53, 53 of mild steel or other suitable magnetic material; these magnet bars extend vertically for one or two feet, this distance depending upon the conditions of operation of the elevator, and they are further provided with inclines 54, 54 which need not be of magnetic material, these inclines forming guide-ramps to prevent the bars from being caught by projections on the elevator car.

The cover 35 of the lock-box fits between the parallel bars 53, 53, as seen in Figure 15; the cover can therefore be removed for inspection without having to detach the bars The parallel magnet bars are also provided upon their rear faces with wedges 55, 55 made of mild steel or other suitable magnetic material, these wedges being attached, as by screws, at positions which bring them to the level of the armature when the parts are assembled. These wedges have their inclined faces directed towards the bevelled faces 51, 51' of the armature, so that when a magnetic circuit is closed upon the magnet bars 53, 53' as hereafter explained, the wedges reduce the reluctance of the circuit through the armature.

Upon the bottom of the lock-box 34, there is mounted an insulating block 56 carrying upon its front face four vertical spring blades 57 58, 59, 60, fixed to the block at their lower ends as by screws, and having metal contact tips 57 58, 59, 60 attached to their upper ends; these spring blades and their contact tips form contact fingers adapted to be con- .nected in pairs by means of bridging segments of conductive material mounted in different planes upon the cylindrical barrel 37. One bridging segment 61 connects the contact fingers 57, 57 and 58, 58' in the normal position illustrated in Figures 5 and 6; in continuation of this segment 61, there in an insulating segment 62 which moves to replace the segment 61 beneath the contact fingers, when the barrel 37 rotates in the anti-clockwise direction (as viewed in Figure 6). The contact fingers 57, 57' and 58, :58, with their bridging and insulating segments 61 and 62, constitute the door contacts indicated conventionally at 9 in Figure 1. An insulating segment 63, arranged towards the right hand end of the barrel (as viewed in Figure 5), normally receives the pressure of the other pair of contact fingers 59, 59 and 66, 60', the circuit between these fingers being thereby interrupted; a second bridging segment 64, arranged in continuation of the segment 63, moves to replace the latter beneath the contact fingers 59, 59 and 60, 60, thereby closing the circuit between these fingers when the barrel rotates as aforesaid; another insulating segment 65, arranged in continuation of the segments 63 and 64, moves to replace the bridging segment 64 beneath the contact fingers 59, 59 and 60, 66', thereb again interrupting the circuit between t ese fingers, when the barrel makes a further rotary mov ment in the same direction. The contact fingers 59, 59' and 60, 60 are included in the circuit of the electromagnetic controlling means for the door locking gear, as hereafter described.

The lever arm 47 0f the armature 50 is also fitted with an interrupting pin 66 extending laterally behind the spring blades 57, 5 8, this pin having an outer sheath 67 of insulating material. The insulated pin 66, 67 operates to deflect the spring blades 57, 58, thereby removing the contact tips 57, 58' from engagement with the segments upon the barrel 37, whenever the lever arm 47 moves forward as a result of the armature 50 being attracted towards the magnet bars; consequently the contact fingers 57 57 and 58, 58" cannot again be bridged by the segment 61 until the armature has returned to normal position, even though the barrel 37 has done so.

An electromagnet for influencing the armature 50 by the establishment of a magnetic circuit through the bars 53, 53 and their wedge-pieces 55, 55', is arranged to move in accordance with the travel of the elevator car, so that the operation of the movable armature of the electromagnetic controlling means will depend upon the presence of the car at the landing in question.

Referring now to Figures 16 and 17, the elevator car C has mounted thereon, for example by means of an angle bracket 68 adjacent to one of its upper corners, a casing 69 of non-magnetic material fitted with a detachable cover plate 70; this casing 69 encloses an electromagnet for controlling the locking gear of the various landing doors giving access to the hatchway. The electromagnet comprises a magnet winding 71 to which electrical connections are led through an aperture 72 in the top of the casing, and a magnet core 73 of U-shape secured to the rear end of the casing as by screw studs 74, 74; the free ends 75, 75 of the magnet core pass through the cover plate 70 and are provided externally with pole-pieces 76, 76 secured for example by set screws. The position of the magnet casing upon the car is such that when the car is resting level with a landing, the pole-pieces 76, 76 are approximately at the middle of the length of the magnet bars 53, 53, mounted upon the lock-box 34 at that landing, as indicated in figure 16, all the lock-boxes being arranged in corresponding positions at the various landings, and that at all times the pole pieces 7 6, 7 6 are approximately in line with the respective magnet bars 53, 53, as indicated in Figure 17, all the pairs of magnet bars being arranged in the same vertical lines at the various landings.

In operation, with the car standing level with a landing, the attempted opening of the landing door causes the electromagnet to become energized, in the manner hereafter described, and subject to the conditions mentioned. The magnetic circuit through the core 7 3 extends from the pole-pieces 76, 7 6 across the air-gaps between the latter and the magnet bars 53, 53, through or along the latter, thence through the wedges 55, 55 and the horn-pieces 51, 51 and through the armature 50; the armature is therefore attracted towards the wedges 55, 55, and the bell crank lever 46, 4&7 is rocked upon its pivot pin 45. It will be noted that any slight error in the levelling of the car with the landing will not prevent the operation, because the vertical run of the magnet bars 53, 53 enables them to convey the magnetic lines of force between the pole-pieces and the wedges 55, 55, in spite of the difference of level. Similarly, if the conditions allow the actuation of the door-releasing means before the car has come to rest, the attraction of the armature 50 can take place as soon as the moving car brings the pole-pieces 76, 76 within range of the upper or the lower ends of the magnet bars 53, 53, according to the direction of travel of the car.

Referring now to the whole of Figures 1 to 17, the operation of the elevator will be briefly described.

In Figure 1, the car is at rest at an intermediate landing L, the operating circuit being broken at the floor controller F. Let it be assumed that the car button 4 is pressed, this serving to close a circuit for the coil of the corresponding floor switch, from the positive main through the door conacts 9", 9, 9, car gate contact 8 (the landing doors and car gate being closed), non-interference switch coil 7, car button 4", floor switrh coil 6", to negative main. The floor switch then operates, closing a circuit for the coil R of the up reversing switch, from positive main, through the door and gate contacts as previously traced, to up reversing magnet coil B, through floor controller contacts F to contacts and coil of ilOU'i' magnet 6, back to negative main.

the reversing switch R Wlll now close, effecting the release of the brake and the operatien of the motor M to raise the car. lVhen the car approaches within a predetermined f'tance of the third landing which is desigby L, the operating circuit is opened by the tioor controller in the well known way. In this manner the circuit to the up winding ll is opened, the reversing switch then opening to disconnect the motor and effect application of the brake to retard and stop the car. When the car-button circuit was made. another circuit was also made through the winding of the car holding and non-interference switch, this constituting the usual car-holding circuit, to prevent anybody else from operating the car from the hall until the arrival of the car at its predetermined landing and the opening of the door contacts.

The floor controller also functions to bring the car to any desired floor in a similar manner by the pressing of a hall button 5, 5' or 5".

Assuming that the car has come to rest at the third landing L, in order to open the door at that landing, the handle 20 or 20 upon the door must be actuated. The initial movement of the handle raises the bolt 17 together with the slotted block 27, by means of linger 22; this initial movement is not suilicient to withdraw the lower end 18 of the bolt from the socket 19, nor is it sufficirnt to lift the slotted block 27 over the shoulder 13 upon the guide rail 12; the door therefore is not yet released. The initial movement does however lift the slotted block 27 sulliciently to cause its extension arm 28 to rock the shaft 31 through a small angle, due to the engagement of the pin 29 with the crank arm 30; this initial rocking movement of the shaft 31 brings the oblique face 42 of the cam 86 into contact with the lug 49 upon the lever arm 47, as shown in Figure 8, their engagement limiting the initial movement of the shaft 31 and therefore of the handles 20, 20.

At the same time the initial movement of the shaft 31 turns the barrel 37 through an equal angle, thereby causing the segment 63 to move away from beneath the contact fingers 59, 59 and 60, 60 giving place to the segment 64, as shown in Figure 11; the segment 61 moves relatively to the contact fingers 57, 57 and 58, 58, but without opening the operating circuit. The passage of the bridging segment 64 beneath the contact fingers 59, 59 and 60, 60 completes a circuit for energizing the electromagnetic controlling means of the door locking gear; this circuit may be traced in Figure 1 as follows :from the positive (-t) main, by lead 90 through the contacts 59 and 60, now bridged by the segment 64 (see Figure 11), by line 91, through the discriminating contacts 92 on the floor controller F (these contacts being now bridged due to the assumed movement of the car to the third landing L), by lead 93, through the pairs of contacts 94, 95 on the reversers R and R, now closed owing to the fact that both of the reversing magnets are now deenergized due to the interruption of the operating circuit, through the flexible lead 97 extending to the elevator car C, through the magnet winding 71, back through the flexible lead 98 from the car, and by way of lead 99 to the negative main. The controlling magnet being thus energized, the armature 50 will be at tracted towards the wedge-fitted magnet bars 53, 53, causing the bell crank lever 46, 47 to rock upon its pivot pin 45 into the position illustrated in Figure 9; it will be noted that the interrupting pin 66 now deflects he spring blades 57, 58, as shown in Figure 13, thereby removing the contact tips 57', 58 from the barrel segments, thus opening the operating circuit as with an ordinary door lock contact to prevent further operation of the elevator until the circuit is again completed. The rocking movement of the bell-crank lever 46, 47 also carries the lug 49 out of engagement with the oblique face 42 of the cam 36; the obstacle to further rotation of the cam 36 being thus removed, the cam and its shaft 31 can now continue their rotation, due to the operation of the handle 20, acting through the bolt 17, slotted block 27, extension arm 28, pin 29 and crank arm 30, attaining the position illustrated in Figure 10. The bolt 17 being now completely raised by this secondary or consequential movement of the latch members, the slotted block 27 is lifted over the shoulder 13 of the guide rail 12, and at the same time the lower end 18 of the bolt is withdrawn from the socket 19; the door can therefore be opened by a sliding movement produced by the continued pressure upon the handle,

the rollers 11, 11 running upon the aide rail 12, and the bottom guide pieces 1 14, 14 sliding in the slot 15 of the sill-plate. The slotted block 27, also travelling along the guide rail 12, maintains the bolt 17 in raised position while the door is being opened and so long as it remains open; the extension arm 28 likewise maintains the shaft 31 in the fully rocked position so long as the door is open.

As already stated, the barrel 37 is pro- 7 \ided with an insulating segment in continuation of the bridging segment 64; when the shaft 31 completes its rotary movement, as shown in Figure 14, this insulating segment 65 replaces the bridging segment 64 beneath the contact fingers 59, 59 and 60, Go in the circuit of the magnet winding 71, thereby interrupting the energizing circuit of the magnet. The interruption of this circuit has for its object to economize current and prevent heating of the magnet winding 71 during the time that the door is open; return movement of the armature 59 is however prevented at this time by the cam 36, the circular contour of which passes behind the lug 49, as shown in Figure 10, to hold the lever arm 47 in the position corresponding to the attracted position of the armature, with the interrupting pin 66 maintaining the deflection of the spring blades 57, 58.

Closure of the door is effected in the usual manner by a sliding movement, the rollers 11, 11 running upon the guide raill2 and the slotted block 27 sliding along the rail until the closed position is reached, when the block 27 slips over the shoulder 13 on to the reduced portion of the rail, allowing the bolt 17 to fall and its lower end 18 to enter the socket 19, thus latching the door, while the handles 20, 20 resume their normal position (see Figures 2 and 5). At the same time the extension arm 28, acting through the pin 29 and crank 30, restores the shaft 31 to normal position, the cam 36 and the barrel 3? rotating back to the position of Figures 5, 6 and 7; the armature 50 falls back to the unattracted position. It will be noted that only upon the return of the armature to normal position, does the interrupting pin 66 permit the contact fingers 57, 57', 58, 58' to re-engage with the barrel segment 61 for closing the operating circuit of the elevator.

It will be seen therefore that the shaft 31 constitutes a mechanical interlocking device between the door bolt releasing means, the electromagnetic lock-controlling means and the doorcontacts in the operating circuit of the elevator, the reclosure of the door-contacts being dependent upon the restoration to normal position of the magnet armature 50 and the shaft 31 which have a positive mechanical interengagement.

It is obvious that any attempt to open the door at a landing, for example the first landing L, at which the car is not present, will fail to operate the locking gear, because the armature 50 can only be attracted by the cont-rolling magnet upon the car when the latter is present at the landing in question. Such attempted opening of the door will pro duce only the initial movement of the bolt and interlocking shaft, bringing the parts to the positions illustrated in Figures 8, 11 and 12, but due to the absence of the car the armature will not disengage the lug 49 of its lever arm 47 from the oblique face 42 of the cam 36, and the further or consequential movement of the releasing means will be prevented. Moreover it will be noted that the initial movement of the bolt and interlocking shaft will not have opened the operating circuit, the segment 61 (see Figure 12) still bridging the contact fingers. It will further be noted that the pressure between the face 42 of the cam and the face of the lug 49 in engagement therewith (see Figure 8) acts directly through the axis of the pivot pin 45 no rocking movement of the bell crank lever can therefore be produced by such pressure, however great the force exerted upon the door handle 20 or 20.

Moreover, the connection of the circuit fer energizing the magnet winding 71 through the controller contacts 94, 95 and through the discriminating contacts as 92 upon the floor controller F determines the energization of the magnet in such a manner that the magnet will not operate unless the car is about to stop and is further intended to stop at the particular landing in question. These conditions prevent the opening of any other landing door by snatching or pressure upon the handle 20 at the moment when the car is travelling past such landing, and thus obviate interference with the regular operation of the elevator as well as accidents liable to be caused by such improper opening of the doors. If the handle at such other landing be actuated, even at the moment when the car is stopping at the particular landing to which it has been directed viz the third), there will be no energization of the electromagnetic controlling means (and therefore the door will not be released) until the actuation of the handle at the third floor landing where the stop is being made. The discriminating contacts upon the floor controller may however be omitted; it is then possible to energize the magnet 71, from any landing when the car is at a standstill. If for example the car is standing at the third floor, and the door handle at the second floor is actuated to the limited extent of its initial movement possible at all times, the magnet 71 will become energized and the armature 50 will be attracted; but owing to the lug 49 engaging the catch 44, movement of the armature will be prevented until the door handle at the third floor has been actuated, lifting the block 27 and rocking the crank arm 30, shaft 31 and catch 44. I

Referring now to Figures 18 to 20, a second form of construction of the elevator door locking gear will be described. The door D suspended from rollers 11 travelling upon the horizontal guide rail 12, is retained in closed position by a fixed beak 101 upon its forward edge, this beak entering a latch casing 102 at the side of the doorway W, wherein it is engaged by a vertically slidable bolt 103; a handle 20 is provided upon each side of the door for releasing the latch, the handles being secured upon a spindle 104 passing through the door. Upon this spindle there are fixed, as by set screws, a finger 105 lying beside the beak 101 and engaging the lower end of the bolt 103, and also a crank arm 106 to which a control spring 107 is attached, the other end of the spring being anchored to a screw 108 inside a housing 109 mounted upon the door. By actuating the handle in order to open the door, and subject to the conditions already recited, the bolt 103 can be lifted by the finger 105 so as to allow the beak 101 to escape beneath the bolt as the door is pulled open; the beak 101 and the lower end of the bolt 103 are bevelled off on their rear faces at 110 and 111 respectively to facilitate their reengagement when the door is again closed.

Towards the top of the doorway and immediately above the bolt 103, there is provided a lock-box 112 made of non-magnetic material, this lock-box being mounted upon the side of the elevator hatchway and secured in any suitable manner. The side of the lockboX nearest to the doorway 1V is apertured at 113 to receive one end of an interlocking bar 114 which extends across the top of the doorway and is supported at its further end upon a pivot pin 115 fixed to the guide-rail 12. The under side of the interlocking bar 114 is notched at 116 to engage a locking pin 117 upon the door when the latter is in the closed position, the bar 114 being then inclined slightly below the horizontal, as seen in Figure 18.

The end of the bar 114 which enters the lock-box is fitted with an angle bracket 118, secured by screws 119, the under face 120 of this bracket having a part-cylindrical boss 121 receiving a screw 122. A contact lever 123, pivotally mounted upon the screw 122, carries a bridge 124 of conducting material secured thereto in an insulating manner by rivets 125 fitted with bushes and washers 126 of insulating material. Upon the other side of the pivot screw 122, the lever 123 has an arm 127 with a cranked extension 128 passing beneath the face 120 of the bracket 118 and above the top end of the bolt 103. A compression spring 129 is engaged between the arm 127 and a lug 130 upon the face of the bracket 118, the spring being held in position by any convenient means and tending to maintain the lever 123, 127 in the position shown in Figure 18 with the bridge plate 124 raised. The contact lever is preferably so designed that its weight causes it to return by gravity to the inclined position, with the bridge plate raised, even if the s ring 129 breaks or fails to act.

In t e interior of the lock-box, there is mounted, as by bosses 131 and screws 132, an insulating block 133 carrying two spring contacts 134, 134 connected by metal strips 135, 135 to binding posts 136, 136, these spring contacts and binding posts being including in the circuit of the magnet winding upon the elevator car, as in the case of the contact fingers 59, 59 and 60, 60' in the previous construction. Sufiicient clearance is left between the extension 128 of the lever arm 127 and the face 120 of the bracket 118 to ensure the closing of the magnet winding circuit before the interlocking bar 114 is raised.

The wall of the lock-box adjacent to the bolt 103 has secured therein, as by screwing, a pin 137 which supports the boss 138 of a lever arm 139, the latter being retained by a washer 140 and split pin or other convenient means, so that the lever arm can rock upon the pin 137. From the boss 138 of the lever 139 there projects a lug 141 having a flat face 142 adapted to engage the end of a pin 143 screwed horizontally into the bolt 103; a tube 144 serving to enclose the bolt 103 between the latch casing 102 and the lock-box 112, extends for some distance into the latter and has its uppen end slotted longitudinally at 145 to allow vertical movement of the pin 143 together with the bolt 103, while preventing any rotation of these parts. The tubular cover also serves to prevent any unauthorized interference or tampering with the locking gear.

The free end of the lever arm 139 is enlarged to form an armature 146, extending across almost the entire width of the lockbox, the lever and armature being made of mild steel or other suitable magnetic material. As best shown in Figure 20, the sides of the armature are bevelled on their outer edges at 147, 147, and its rear face has a projection 148 reinforced by a stiflening web 149. This projection 148 is so placed as to rest above the end of the interlocking bar 114 inside the lockbox 112 when the armature 146 is in its normal unattracted position, as shown in Figures 18 and 19, thus preventing the pivotal movement of the bar 114; the lever arm 139 of the armature is itself locked by the engagement of the lug 141, 142 with the pin 143 so long as the bolt 103 is not raised by the initial opening movement of the door-handle.

As in the previous construction described, two parallel magnet bars 53, 53 are secured upon the front of the lock-box, for example by screws, these bars being of mild steel or other magnetic material and extending vertically for a suitable distance depending upon the conditions of operation; the magnet bars are also provided with inclines (not shown) at their upper and lower ends, as in the previous case. The cover 35 of the lock-box fits between the parallel bars 53, 53, being secured in a detachable manner, as by screws.

The rear faces of the parallel magnet bars are likewise provided with wedges 55, 55' of magnetic material, at positions level with the armature 146 in assembled position, these wedges also having their inclined faces directed towards the bevelled faces 147, 147 of the armature, so as to form part of the mag netic circuit through the armature.

The armature is further provided upon its rear face with an insulated bridge-plate 151 of conducting material, secured as by screws; behind this bridge 151 and upon the rear wall of the lock-box, there is mounted an insulating block 152 carrying spring contacts 153, 153 respectively connected by strips 154, 154' of conducting material to binding posts 155, 155 included in the operating circuit of the elevator. The arrangement is such that when the armature is in the normal unattracted position, the plate 151 bridges the contacts 153, 153, thus closing the operating circuit at this point, as with the usual door lock contacts.

The operation of the locking gear is substantially the same as in the previous case. With the car at rest at a landing, the attempted opening of the door by means of the handle 20 raises the bolt 103 and rocks the lever 123, 127 until the cranked extension 128 abuts against the under face 120 of the angle bracket 118 upon the interlocking bar 114, the lifting of the latter being as yet prevented by the overhanging projection 148 upon the rear of the armature 146. The rocking movement of the lever 123, 127 is sufficient to bring the conducting plate 124 into engagement with the spring contacts 134, 134, thus bridg ing these contacts and completing the circuit for the magnet winding 71, as described in the previous construction. The energization of the electromagnet attracts the armature 146 towards the magnet bars 53, 53 and their wedges 55, 55, thereby rocking the lever arm 139 in a clockwise direction (as viewed in Figure 19) the rocking movement of the lever arm 139 is no longer prevented by the lug 141, because the raising of the bolt 103 has caused the pin 143 to slide vertically over the face 142 of the lug to a position clear of the latter. The movement of the armature 146 carries the bridging plate 151 away from the spring contacts 153, 153', thereby interrupting the operating circuit at thls point and preventing the operation of the elevator, in the well known manner; at the same time the movement of the armature withdraws its projection 148 from above the interlocking .the door-handle bar 114. The obstacle to the rise of the bar 114 being thus removed the belt 103 can continue its upward motion due to the operation of the handle 20, acting through the finger 105, so as to clear the beak 101 and allow the opening of the door; at the same time the bolt 103 raises the extension 128, lever 123, 127, bridge plate 124, and angle bracket 118, to gether with the adjacent end of the interlocking bar 114, the latter pivoting upon its other end at 115 and raising its notch 116 clear of the locking pin 117 upon the door. The latter can therefore be opened by a siiding movement, the locking pin 117 travelling along with the door and holding up the bar 114; the end of this bar enclosed in the lock box, being now raised behind the extremity of the projection 148, prevents the return of the armature and the re-closing of the operating circuit so long as the door remains open.

It will be noted that when the second part of the movement of the bolt 103 takes place, the lifting of the contact iever causes its bridge plate 1:24 to interrupt the circuit of the electromagnetic controlling means, thus avoiding waste of current during the time that the door remains open. The de-energization of the magnet winding however does not result in a return movement of the armature 146, because the lifting of the interlocking bar 114 causes its end enclosed in the loci;- box to rise behind the extremity of the projection 148, thus retaining the armature in the attracted position in spite of the de-energization of the electromagnet.

\Vhen the door is re-closed, the locking pin 117 travels with the door, maintaining the interlocking bar 114 raised until the door reaches its closed position, whereupon the notch 116 reengagcs over the pin and allows the bar to fall, while the beak 101 first lifts the bolt 103 by the sliding contact of their bevel faces 110, 111, and then allows the bolt to re-engage over the beak, thus locking the door in closed position. At the same time the dropping of the bar 114 removes the obstacle to the return movement of the armature 146, which resumes the position shown in figure 19, its projection 148 re-engi'aging above the bar 114 and its plate 151 bridging the contacts 153, 153 to re-close the operating circuit in readiness for the starting of the elevator; the descent of the lever 123, 127 with the angle bracket 118 and interlocking bar 114 has no effect as regards the closure of the magnet energizing circuit through the contacts 134, 134', because the spring 129 rocks the lever to the position shown in Figure 18 as soon as the support from the top end of the bolt 103 is withdrawn.

It will be understood that although the operations following upon the actuation of have been described as taking place in successive stages for the sake of clearness, the opening movement of the handle is practically continuous, the check imposed by the interlocking device being imperceptible, provided that the required conditions for the release of the door-retaining means fulfilled. This applies not only to the construction represented in figures 18 to 20. but also to the previous construction described with reference to Figures 2 to 15. Ey setting the contacts of the electromagnetic controlling means so that they are closed shortly before the mechanical interioci-iing device can produce the momentary arrest of the releasing means, the resulting attraction of the armature may be arranged to free the mechanical interlock before such arrest takes place, so that there is no check to or interruption of the releasing movement, subject to the conditions mentioned; in this case the stage of operation represented in Figure 8 will be suppressed in normal working, and the cam 86 will not be blocked or ared by the engagement of its face 42 with 0 unless the energization of the elecn, g ic controlling means has failed, due for example to the elevator car not being in nded to stop at the landing in question.

er to reduce the width of the airs) 01 gaps between the pole-pieces of the lock-controlling electroinagnet upon the car and the magnet bars provided in the vicinity of the iofzoings, and in order to allow for possible awaying movements of the car, there may be employed the construction of electromagnetic controlling means illustrated in Figures 21 and in this arrangement, the elevator car C has mounted thereon, for example by means of a T-shaped bracket 156 adjacent to one its upper corners, a pair of parallel levers 1i of equal length swinging upon ver- 1J1 tical pivot pins 158, 158' screwed or otherwise secured to bosses 159, 150 at opposite extremities of the T-piece; the lovers are held upon the pins 158, 158 as by washers and split pins, and their ends 160, 160 are piv otally connected as by screws 161, 161 to the undersideof a casing 162 whitis made of non-magnetic material and encloses the controlling electromagnet winding 71 with magnet core 73 as in the construction illustrated in figures 16 and 17. The swinging levers 157, 157 provide a parallel mot on whereby the magnet casing 162 can swing in the horizontal piano in a direction to the right or to the left (as viewed in Figure 22), that is, transversely to the vertical lines of the mag net oars 53, 53. The free ends of the magnet core are provided externally of the casing 162 w h pole-pieces 163, 163 of magnetic material, which may be integral with the respective limbs of the magnet core, these pole-pie es being notched vertically as seen in Figure 22 at 164, 164'. The magnet bars 53, 53 are of L-section, having flanges 165, 165' respectively, which enter the notches 164, 164 of the pole-pieces 163, 163; the notched ends of the pole-pieces thus form guiding forks engaging the sides of the flanges 165, 165 and maintaining the magnet casing 162 in definite relation to the vertical lines of the parallel magnet bars, in spite of any lateral swaying of the car. Movement of the car in the perpendicular direction merely affects the depth to which the notches 164, 164 engage the flanges 165, 165, without altering the width of the air gap. in the former construction described.

As previously explained, the magnet bars 53, 53 extend vertically for a suitabie distance above and below the magnet pole-pirces when the car is at rest level with the landing. To provide continuous engagement with the notched pole-pieces 163, 163 during travel of the car between landings, the magnet bars at the various landings are connected in acontinuous manner by intermedite L-section ;bars 166 as shown in Figure 21; these intermediate bars may be of non-magnetic material, or as illustrated spacer blocks 167 of non-magnetic material may be interposed between the magnet bars 53, 53 and the intermediate bars 166 to limit the magnetic flux to the vicinity of the lock-box 34 correspond ing to the landing at which the car is standing. The junctions between the magnet bars 53, 53, intermediate bars 166, and spacer blocks may be supported by suitable brackets 168 bolted or otherwise attached to the wall of the hatchway.

Figure 21 shows how the swinging levers 157, 157 may be provided with extensions 169, 169' upon the opposite side of the pivot pins 158, the extensions forming counterweights as at 170, 170 for balancing the Weight of the magnet casing 162 and the parts carried thereby.

It will be noted that the invention provides a locking gear in which the parts are connected together in a positive manner by mechanical interlocking devices, and that the various parts are arranged to return by gravity to their normal position, corresponding to the latching of the door, compression springs be ing utilized if desired to assist their movements in this sense.

Emergency means may be provided for allowing the opening of the landing doors in the event of failure of the power supply for the electromagnet upon the car. so that in the case of a fire for example the passengers may still be able to leave the car. For this purpose We have shown the bell crank lever 46, 47 in Figure 6 fitted with an arm 46 to permit the rocking of the bell crank by hand from the exterior of the box after a suitable sealing member has been broken. Figures 23 and 2 4 illustrate an arrangement for this purpose.

A vertical push-rod 171 adapted to engage the lever arm 46 and enclosing in a guide tube 172 extending down from the 1ock-box 34, rests at its lower end upon a small lever 17 3 secured to a rotatable spindle 174 mounted in a casing 175 fixed to the wall of the hatchway. The front of the casing 175 is protected by a glass cover 176 normally preventing access to the spindle, which has for example a square end. In an emergency the device may be brought into operation by the attendant or passenger in the car C, by breaking the sealing cover 176 and inserting a suitably shaped key 177 through the aperture so as to engage the spindle 174, it being thus possible to operate the lever 173 so as to raise the push rod 171 and to rock the bell crank lever 46, 47 for the purpose of moving the armature 5O forward into its attracted position (see Figure 9), thus permitting the full operation of the handle to release and open the door. The same emergency device can also be utilized by a person on the land ing, the casing 175 having an extension tube 178 passing through the wall and terminating in a circular frame 179 fitted with a glass cover piate 180. By breaking this glass plate and inserting a suitable shaped key 181, the inner end of the spindle 174 can likewise be engaged to allow operation of the lever 173, push-rod 171 and bell crank 46, 47 to move the armature into its attracted position.

WVhat we claim is 1. Elevator door locking gear, comprising means for latching the door in closed position, means for locking said latching means, and electromagnetic means for releasing said locking means, said electromagnetic releasing means including a magnet moving in accordance with the travel of the elevator car. i

2. Elevator door locking gear, comprising means for retaining the door in closed position, manually operable means for releasing said retaining means and opening the door, an electromagnet moving in accordance with the travel of the elevator car, and an armature adapted to be attracted by said electromagnet when the car is level with the landing, said manually operable releasing and dooropening means being controlled by said armature.

Elevator door locking gear, comprising individual means for retaining each of the landing doors in closed position, means for releasing each of said retaining means, means normally locking said releasing means against operation, and a single unlocking device mounted upon the elevator car, said unlocking device being adapted to unlock the releasing means for any landing door without I11 chanicai connection between said unlocking device and said means normally locking said releasing means.

Elevator door locking gear, comprising individual means for retaining each of the landing doors in closed position, means for releasing each oi said retaining means, means norm ally locking said releasing means against operation, and a single unlocking device mounted upon the elevator car, said unlocking device being adapted to unlock the releasing means for any landing door without mechanical connection between said unlocking device and said means normally locking said releasing means, the operation of said unlocking device being dependent upon the stopping of the car at the landing in question.

Elevator door locking gear, comprising means for retaining the door in closed position, means for releasing said retaining means, a mechanical interlocking device tending in line with the movement of the door, positive connecting means between said releasing means and said interlocking; device whereby said interlocking device is displaced by the operation of said releasing means, means for retaining said interlocking device in displaced position so long as the door re nains open, said releasing means'being there by retained in operated position, and means for preventing operation of the elevator until the return of said interlocking device and said releasing means to normal position.

6. Elevator door locking gear, comprisinq means for retaining the door in closed pos. tion, means for releasing said retainini: means, an interlocking bar extending acres the opening for the door, a mechanical connection between said releasing means and said interlocking bar, said mechanical connertion causing displacementof said int 1 ing liar by the operation of said rele means, means for retaining said rel,- I ineans in operated position so long as said tcrlocking bar remains tlisplilCitl, means for retaining said interlocking bar displaced st long as in door remains open, and means for preventing operation of the elevator until the return of said interlocking bar to normal position.

7. Elevator door locking gear, compri ng means for retaining the door in closed position, means for releasing said retaining Lneans, an interlocking bar extending Miss the opening for the door, means for displacin sa' interlocking bar by the operation of l releasing means, a member travellin with. the door and retaining said interlockii iitll displa: so long as the door rmaius open. and means for preventing operation of the elevator until the return of said interlocking bar to normal position.

8. Elevator door locking gear compr means tor locking the door in closed position, manually operable means lor releasing said locking means and opening said door, anl electromagnetic means for controlling said releasing and opening means, said electromagnetic controlling means depending for its operativeness upon the presence of the elevator car at the landing in question and upon the intention to stop the car at said landing.

9. Elevator door locking gear, comprising means for retaining the door in closed position, manually operable means for releasing a a d opening said door, an electromagnct moving in accordance with the travel of the elevator car, an armature adapted to be attracted with the landing, said manually operable releasing and door-opening means being controlled if said armature, and a mechanical device for interlocking said armature with said manually operable means.

it), Elevator door locking gear, (fOl'llPllS- mca" s for retaining the door in closed pi'nlion, manually operable means for reand opening said door, an electromagnet moving in accordance with the travel oil the elevator car, an armature adapted to be attracted by said electromagnet when the ar is level with the landing, said manually operable releasing and door-opening means liming controlled by said armature, and a mechanical device for interlocking said manually operable means when the door is in open position.

11. Ele 'ator door locking lag means for retaining the door in closed p ion, manually operable means for rels ig and opening said door, an electromagnet moving in accordance with the travel oi the e evator car, an armature adapted to be attracted b said electromagnet when the ar level with the landing, said manually op able releasing and door-opening means bongcontrolled by said armature, and mech cal means for interlocking said armature with said manually operable means and d manually operable means when the door is ,n open position.

la vator door locking gear, comprising means for retaining the door in closed pos tion, means for releasing said retaining means, said releasing means having an initial movement possible at all times, and means for controlling further movement of said releasing means, said controlling means being dependent upon the presence of the elevator car at the landing in question, upon the, intention to stop the car at said landing, and upon the init al n'mvenunt ot said rcleai'ting means.

13. Elevator door locking gear, comprismeans for retaining the door in closed pos tion, means for releasing said retaining means, said releasing means having an initial movement possible at all times, an electromi, me s for controlling inrther movement oi? said releasing means, said lectromagnetic means being dependent upon the initial nrwement of said releasing means.

av said electromagnet when the car is level 14. Elevator door locking gear, com'irising means for retaining the door in closed position, means for releasing said retaining means, said releasing means having an initial movement possible at all times, electromagnetic means for controlling further movement of said releasing means, and contacts included in the exciting circuit of said electromagnetic means, said contacts being closed by the initial movement of said releasing means.

15. Elevator door locking gear, comprising means for retaining the door in (ill Willi position, means for releasing said retaining means, said releasing means having an initial movement possible at all times, electromagnetic means for controlling further movement of said releasing means, and contacts included in the exciting circuit of said elco tromagnetie means, said contacts being closed by the initial movement of said re leasing means, and opened by the further movement of said releasing means.

16. Elevator door locking gear, comprising means for retaining the door in closed position, means for releasing said retaining means, said releasing means having an initial movement possible at all times, and electro magnetic means for controlling turther movement of said releasing means, said electromagnetic controlling means being momentarily excited by a circuit closed by the initial movement of said releasing means and interrupted by the further movement of said releasing means.

17. Elevator door locking gear, comprising means for retaining the door in closed position, means for releasing said retaining means, said releasing means having an initial movement possible at all times, and electro magnetic means for controlling the further movement of said releasing means, said electromagnetic controlling means depending for its operativeness upon the p 'esence of the elevator car at the landing in question, upon the intention to stop the car at said landing, and upon the initial movement of said releasing means.

18. Elevator door locking" gear, comprising means for retaining the door in closed position, means for releasing said retaining means, said releasing means having an initial movement possible all times. an electromagnet moving in accordance with the travel of the elevator car, and an armature adapted to be attracted by said electromagnet when the car is level with the landing. said armature controlling further movement of said releasing means, and the excitaiion of said electroinagnet being dependent upon the intention to stop the car at the landing in question.

19. Elevator door locking gear, comprising means for retaining the door in closed position, means for releasing said retaining means, said releasing means having an initial movement possible at all times, an electromagnet moving in accordance with the travel of the elevator car, and an armature adapted to be attracted by said electromagnet when the car level with the landing, said armature controlling further movement of said releasing means, and the excitation of said clectromagnet being dependent upon the intention to stop the car at toe landing in question and also upon the initial movement of said releasing means.

2.). Elevator door locking gear, compris ing means for retaining the door in closed position, means for releasing said retaining means, said releas'ng means having an initial movement possible at all times, an electro magnet moving in accordance with the travel of the eleva or car, and an armature adapted to be attracted by said electromagnet when the car is level with the landing, said armature controlling further movement of said means, said electromagnet being momentarily exclted by a circuit closed by the initial movement of said releasing means and interrupted by the further movement of said releasing means.

l llevator door locking gear, comprising mcans for retaining the door in closed position, means for releasing said retaining icons, said releasing means having an initial movement possibl at all times, and electro magnetic means for controlling further movement of said releasin'g means, said electron'iagnelic controlling means depending for its operati-veness upon the presence of the elevator car at the landing in question and upon the intention to stop the car at said landing and being excited by a circuit closed by the initial movement of said releasing means and interrupted by the further movement of said releasing means.

22. Elevator door locking gear, comprising means for retaining the door in closed position, means for releasing said retaining means, said releasing means having an initial movement possible at all times, a mechanical interlocking device normally preventing further movement of said releasing means, electromagnetic controlling means for said interlocking device, the operation of said electromagnetic controlling means allowing said mechan cal interlocking device to permit said further movement of said releasing means, and means tor energ zing said electromagnetic controlling means. i

23. Elevator door locking gear.v comprising means for retaining the door in closed posit on, means for releasing said retaining means, said releasing means having an initial movement possible at all times, a mechanical interlocl-Iing device normally preventing further movement of said releasing means. electr ma netic controlling means for said interlocking device, the operation of said electromaginetic controlling means allowing said mechanical interlocking device to permit said further movement of said releasing means, and means tor energizing said electromagnetic controlling means upon said initial movement, subject to the stopping of the elevator car at the landing in question.

24, l llevator door locking gear, comprising means for retaining the door in closed {)Qtmtl-Oll, means for releasing said retaining means, said releasing means having an initial movement possible at all times, a mechanical interlocking device normally preventing further movement of said releasing means, an electro-magnet moving in accordance with the travel of the elevator car, an armature adapted to be attracted by said electromagnet when the car is stopping level with the landing in question, a catch operated by said armature, said catch co-operating with said mechanical interlocking device, the attraction of said armature withdrawing said catch to allow said interlocking device to permit iurthcr movement of said releasing means, and means for energizing said electromagnet upon said initial movement of said releasing means.

Elevator door lo king gear, comprising means for retaining the door in closed position, means for releasing said retainin means, said releasing means ha 'ing an initial movement possible at all times, a mechanical interlocking device normally preventing further movement of said releasing means, electromagnetic controlling means for said interlocking device, the operation of said electromagnetic controlling means allowing said mechanical interlocking device to permit said further movement of said releasing means, and means for energizing said electromagnetic controlling means upon said initial movement, said electromagnetic controlling JtZlYlS dcpe ,ding for its operativeness upon the presence of the elevator car at the landing in question, said electromagnetic controlling means being tie-energized upon said further movement of said releasing means.

26. Elevator door locking gear, comprising means for retaining the door in closed position, means for releasing said retaining means, said releasing means having an initial movement possible at all times, a mechanical interlocking device normally preventing further movement of said releasing means, clcctronn gnetic controlling means for said interlocking device, the oiieration of said electro-magnetic controlling means allowing mechanical interlocking device to permit said turther movement of said releasing means. means for energizing said electromagnetic controlling means upon said initial movement, said electromagnetic controlling means depending for its operativeness upon the presence or the elevator car at the landing in question, said electromagnetic controlling means being (lo-energized upon said further movement or said releasing means, and means for holding said mechanical interlocking de vice against return movement while the door is open.

27. Elevator door locking gear, comprising means for retail ing the door in closed position, means for releasing said retaining means, an electron'iagnet moving in acordance with the travel of the elevator car, an armature adapted to he attracted by said elec romagnet when the car is stopping at the landing a mechanical interlocking device normally preventing operation of said releasing means, said armature controlling said mechanical interlocking device, means for energizing said electromagnet to allow said mechanical interlocking device to permit operation of said releasing means, means for preventing movement of the car while said releasing means remain operated, and means for holding said mechanical interlocking device against return movement while the door is open.

28. Elevator door locking gear, comprising means for retaining the door in closed position, means for releasing said retaining means, electromagnetic means "For controlling said releasing means, said electromagnetic means depending for its operativeness upon the stopping of the elevator car at the land ing in question, a mechanical interlocking device normally ncventing operation of said releasing means, the operation of said electromagnetic controlling mcans allowing said m chanical interlocking device to permit operation of said releasing means, and means for holding said mechanical interlocking dc vice against return movement while the door is open.

29. Elevator door locking gear, comprising means for retaining the door in closed position, means for releasing said retaining means, electromagnetic means for controlling said releasing means, said electromagnetic means depending for its oporativeness upon the stopping of the elevator car at the landing in question, a mechanical interlocking device normally preventing operation of said releasing means, said mechanical interlocking device extending along the line of movement of the door, the operation of said electromagnetic controlling means allowing said mechanical interlocking device to permit operation of said releasing means, and a member moving with the door, said member holding said mechanical interlocking device against return movement while the door is open.

30. Elevator door locking gear, comprising means for retaining the door in closed position, means for releasing said retaining means, an interlocking device normally preventing the operation of said releasing means, electromagnetic means for controlling said 

